1. Field of the Invention
The present invention relates, in general, to a method of searching for a sync start in an automated manual transmission, and more particularly, to a technology for searching for a sync start, i.e. a point at which actual synchronization starts, when a shifting operation is carried out using an actuator in an automated manual transmission mechanism of the related art, such as a dual clutch transmission (DCT) or an automated manual transmission (AMT).
2. Description of Related Art
In a transmission mechanism using a manual transmission of the related art, when a shifting operation is started following a selecting operation, a sleeve in a neutral position linearly slides in the direction in which a target gear is positioned. At the same time, a key pushes a synchronizer ring so that the synchronizer ring abuts against a cone of a clutch gear, thereby starting synchronization. When the synchronization is completed, the sleeve meshes with the clutch gear through the synchronizer ring, thereby completing shifting to the target gear.
In an automated manual transmission, the above-described shifting operation is carried out by a shifting actuator. In order to satisfy conflicting requirements including rapid shifting response and smooth shifting sensation, the shifting operation using the shifting actuator is controlled such that the sleeve is moved as rapidly as possible before the sync start where the synchronizer ring starts adjoining the cone of the clutch gear, and afterwards, is moved slowly using as smooth a movement as possible until the synchronization is completed.
If the sync start is erroneously estimated, for example, if, in controlling the shifting actuator, the sync start is estimated to be a point that is too close to the neutral position, the sleeve must also be moved to the sync start, which increases a shifting time, thereby degrading the response. In contrast, when the sync start is estimated to be a point that is too far from the neutral position, a shifting impact occurs.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.